Scalatest "At least one" instead for Forall

Question

I wrote this test method in Scala to test a REST service.

@Test def whenRequestProductInfo() {
  // When Request Product Info
  forAll { (productId: Int) =>
      val result = mockMvc().perform(get(s"/products/$productId")
        .accept(MediaType.parseMediaType(APPLICATION_JSON_CHARSET_UTF_8)))
        .andExpect(status.isOk)
        .andExpect(content.contentType(APPLICATION_JSON_CHARSET_UTF_8))
        .andReturn;

      val productInfo = mapper.readValue(result.getResponse.getContentAsString, classOf[ProductInfo])

      // At least one is not null
      // assert(productInfo.getInventoryInfo != null)
  }
}

But I want to test that at least one productInfo.getInventoryInfo is not null instead of every productInfo.getInventoryInfo is not null.

Answer 1

Assuming we have a list of product ids:

val productIds: List[Int] = ???

We ought to factor the conversion from productId to productInfo into another val. (I would think this method or something similar would exist in your code elsewhere).

val inventoryInfo = productIds.map { case productId =>
    val result = mockMvc().perform(get(s"/products/$productId")
        .accept(MediaType.parseMediaType(APPLICATION_JSON_CHARSET_UTF_8)))
        .andExpect(status.isOk)
        .andExpect(content.contentType(APPLICATION_JSON_CHARSET_UTF_8))
        .andReturn

    val productInfo = mapper.readValue(result.getResponse.getContentAsString, classOf[ProductInfo])
    productInfo.getInventoryInfo
 }

Now we have a list of inventory info, whatever type that is. We can use atLeast to check that at least one inventory info from the collection is not null.

atLeast(1, inventoryInfo) should not be null

It doesn't seem like ScalaTest has any curried version of this like with forAll, so the syntax is much different and not quite as nice if you need to do a bunch of computations.